Robust fibrillar nanocatalysts based on silver nanoparticle-entrapped polymeric hydrogels

Robust fibrillar network of hydrogels entrapped with silver nanoparticles were prepared by in situ polymerization of acrylic acid and reduction of silver nitrate using amidodiol as cross-linking cum reducing agent under ambient conditions. Silver nanoparticle-entrapped polyacrylic acid-amidodiol hydrogels (SPAGs) were characterized by UV-visible spectroscopy, SEM, TEM, XRD and rheology. Further, catalytic activities of SPAGs were studied using dyes such as methylene blue, rhodamine 6G and crystal violet. Effects of temperature and pH on the reduction process were studied. The activation energy for the reduction process was calculated and found to be decreased by ~10 kJ/mol in the SPAG-catalysed reaction. In addition, SPAGs showed excellent reusability, easy separation, high rate constant and absence of induction period. All these results suggested SPAGs as a promising catalyst for the reduction of organic molecules.